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There is not any “official” or “universal” Noahide liturgy for any defined prayer services. On a deeper level, this is really as it should be, because a fixed liturgy could give a Noahide the mistaken impression that he or she has a religious requirement to recite specific prayers at set times of day, or at set days on the calendar, which is not the case. Rather, the minimum obligation of prayer for a Noahide is that when you recognize that you have a need, you should direct your mind to G-d and pray to Him to fulfill that need.[1] When you do that, you can gain even more merit at the same time by having full trust and faith that He hears your prayers and that He will answer in a way that will be truly and openly good for you.* Similarly, when you feel religiously inspired or motivated and want to pray, that prayer should be directed only to the One True G-d, and it can include praising Him and thanking Him,
Although G-d knows all the thoughts of a person, it is most appropriate that your prayers should be verbalized with the mouth (since only that is called “prayer”), at least loudly enough so that you can hear your own speech. In that way not only your mind but also your body is praising and praying to G-d, as we are told to do in many verses of the Psalms.
If you are making a personalized collection of prayers, it is appropriate to make selections from the Psalms (“Tehillim” in Hebrew). It’s best to get the Psalms from an authentic Hebrew Bible/Tanakh or a Book of Psalms/Tehillim or other publication that is from an observant Jewish publishing company. It’s also good if it can be a translation in the language you best understand, if possible.
King David composed and compiled the entire Book of Psalms to reflect every emotional dimension that a spiritually directed person could experience. You are certainly free to choose any Psalms which seem most appropriate for the feelings you wish to convey to G-d.
To assist Noahides in their daily prayers, Ask Noah International has published booklets of daily prayers for Noahides, in several languages. The title in English is
“Prayers, Blessings, Principles of Faith, and Divine Service for Noahides,” by Rabbi Moshe Weiner and Rabbi J. Immanuel Schochet:
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